2 Copyright (C) 2003-2013 Paul Brossier <piem@aubio.org>
4 This file is part of aubio.
6 aubio is free software: you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation, either version 3 of the License, or
9 (at your option) any later version.
11 aubio is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with aubio. If not, see <http://www.gnu.org/licenses/>.
25 This object implements a phase vocoder. The spectral frames are computed
26 using a HanningZ window and a swapped version of the signal to simplify the
27 phase relationships across frames. The window sizes and overlap are specified
30 \example spectral/test-phasevoc.c
34 #ifndef AUBIO_PHASEVOC_H
35 #define AUBIO_PHASEVOC_H
41 /** phasevocoder object */
42 typedef struct _aubio_pvoc_t aubio_pvoc_t;
44 /** create phase vocoder object
46 \param win_s size of analysis buffer (and length the FFT transform)
47 \param hop_s step size between two consecutive analysis
50 aubio_pvoc_t * new_aubio_pvoc (uint_t win_s, uint_t hop_s);
51 /** delete phase vocoder object
53 \param pv phase vocoder object as returned by new_aubio_pvoc
56 void del_aubio_pvoc(aubio_pvoc_t *pv);
58 /** compute spectral frame
60 This function accepts an input vector of size [hop_s]. The
61 analysis buffer is rotated and filled with the new data. After windowing of
62 this signal window, the Fourier transform is computed and returned in
63 fftgrain as two vectors, magnitude and phase.
65 \param pv phase vocoder object as returned by new_aubio_pvoc
66 \param in new input signal (hop_s long)
67 \param fftgrain output spectral frame
70 void aubio_pvoc_do(aubio_pvoc_t *pv, const fvec_t *in, cvec_t * fftgrain);
71 /** compute signal from spectral frame
73 This function takes an input spectral frame fftgrain of size
74 [buf_s] and computes its inverse Fourier transform. Overlap-add
75 synthesis is then computed using the previously synthetised frames, and the
78 \param pv phase vocoder object as returned by new_aubio_pvoc
79 \param fftgrain input spectral frame
80 \param out output signal (hop_s long)
83 void aubio_pvoc_rdo(aubio_pvoc_t *pv, cvec_t * fftgrain, fvec_t *out);
87 \param pv phase vocoder to get the window size from
90 uint_t aubio_pvoc_get_win(aubio_pvoc_t* pv);
93 \param pv phase vocoder to get the hop size from
96 uint_t aubio_pvoc_get_hop(aubio_pvoc_t* pv);
100 \param pv phase vocoder to set the window type
101 \param window_type a string representing a window
103 \return 0 if successful, non-zero otherwise
106 uint_t aubio_pvoc_set_window(aubio_pvoc_t *pv, const char_t *window_type);
112 #endif /* AUBIO_PHASEVOC_H */